Electric hair drier



May 26, B, A BENSON ELECTRIC HAIR DRIER Filed July 1, 1935 2 Sheets-Sheet l Inve tor.

May 26, 1936. B. A. BENSON ELECTRIC HAIR DRIER Filed July 1, 1955 2 Sheets-Sheet 2 0 0 r 0 a C r a n e 0 v r Q8 13 Patented May 26, 1936 UNl'i'ED STATES PATENT OFFICE ELECTRIC HAIR- DRIER Application July 1, 1935, Serial No. 29,218

12 Claims.

My invention relates to an electric hair drier of the class in which a motor-driven blower forces air through a casing and past an electric heating unit through a spout-forming part of 5 the casing, such hair driers being commonly constructed either in handled types adapted to be held in a hand of the user, or in stationary types in which a pedestal is substituted for the handle. Heretofore, such hand-held hair driers commonly have been constructed with two casings, one of which houses the fan and blower and also affords the spout in which the heating element is disposed, while the other casing houses the electric motor for rotating the fan. With such constructions, the supporting handle usually underhangs only one of the twoseparately constructed casings, and the heating unit is fastened to the spout which houses it.

In practice, such constructions have had the following objections:

(1) To aid the user in projecting the blast of air in the desired direction, the handle usually underhangs the fan-housing casing and has its axis in a plane diametric of both the air spout and the fan casing. Consequently, the electric motor--which is by far the heaviest constituent unit of the hair drieris offset sidewise from this medial plane to such an extent that the weight of the motor continually tends to tilt the hand which holds the handle, thereby unduly tiring the user.

(2) If the supporting handle underhangs only the fan-housing casing so that the handle can have its axis in a vertical diametric of the tubular portion of this main casing, both the second casing and the motor housed by the latter are far from the said plane. Consequently, the off-side disposition of this motorwhich in practice is 4 by far the heaviest constituent unit of the entire appliance-continually tends to tilt the hand which supports the electric hair drier by its handle, so that the resulting strain unduly tires the user. 45 (3) On the other hand, if the handle underhangs the motor so that this handle has its (generally upright) axis spaced laterally by a consid erable distance from a vertical plane along the axis of the said tubular portion of the main casing, it is diflicult for the user to direct the discharge of air in the desired direction, and particularly so when this user is wanting to dry the upper or rearward portions of her own hair.

(4) The providing of a complete casing for the fan and of at least one additional casing Cir member for housing the motor, together with the means for fastening these parts to each other, add undesirably both to the Weight and the cost of the hair drier.

(5) The fastening of the electric heating unit to the spout increases the difficulty of providing the current connections to this unit, and of replacing that unit in case the heating element burns out.

(6) The general assembly of such an electric hair drier usually involves an undesirably large cost for the constituent parts and for their assembly, and also usually requires an adequately powerful electric hair drier to be so bulky as to make it difiicult for the hair dresser to see some portions of the hair against which warm air is directed by the hair drier.

('7) For inexpensive electric hair driers, it is desirable to use a simple type of self-starting alternating current motor, such as has been highly developed for use with fan motors. However, the usual running speed of such motors is so high that even a simple blower vane when fastened directly to the shaft of the motor will propel the air so rapidly past the heating unit, that this air will not be adequately heated if all of the air was propelled directly by the motor.

In its general objects, my invention aims to overcome all of the above recited objections, and also aims to provide an electric hair drier from which the entire casing can be easily and speedily detached for access to its mechanism, without disassembling other parts.

More particularly, my invention aims to provide an electric hair drier of the recited class, having the following advantageous features:

(a) A single casing comprising two generally counterpart casing halves, one of which can readily be detached from the other for inspecting the heating element, and for replacing the heating unit when necessary.

(b) Disposing the entire mechanism of the hair drier so that its center of gravity will be at a relatively short distance from a vertical plane in which both the axis of the handle and that of the tubular casing portion are disposed, thereby eliminating the hand-twisting strain encountered with the hair driers heretofore in use.

(0) Providing a simple partition within this casing between this motor and the fan, in substitution for another casing part, and using this partition as a support for one of the bearings of the motor.

(11) Perforating this partition and disposing the partition approximately in a plane diametric of the spout of the hair drier, so that the fan will directly propel air entering at one side of the casing and so that the movement of this air will suck additional air in at the other side of the casing, whereby this suction effect slows the movement of air past the heating unit.

(e) Constructing the partition so that it can be fastened to the motor and so that the partition will interfit a portion of the non-detachable casing half to aline the two bearing supports.

(1) Providing rigid means for supporting the electric heating unit solely from this partition.

(9) Using the non-detachable casing half as a part of the support for the other bearing of the motor.

(h) Arranging the mechanism so that the motor, partition and heating unit can be initially connected as a unitary assemblage of parts, and so that this assemblage can thereafter be fastened to the non-detachable casing half from the exterior of the latter.

(i) Providing the motor with a bridge constructed for clamping one bearing against a side of the non-detachable casing half when the motor is being fastened to that part of the casing.

(7') Providing for a convenient lubricating of both bearings without requiring the detaching of any part of the hair drier.

(k) Arranging the mechanism so as to afford a considerable reduction of its cost, weight and bulk from that of heretofore commercial hair driers of the same class.

Illustrative of the manner in which I accomplish the above as well as more detailed objects of my invention,

Fig. 1 is a perspective view of a handled electric hair drier embodying my invention.

Fig. 2 is a plan view, and Fig. 3 a front elevation of the same.

Fig. 4 is an enlarged longitudinal section through the same hair drier, taken along the line 4-4 of Fig. 3.

Fig. 5 is a fragmentary longitudinal section, taken generally along the line 5-5 of Fig. 4, but with the motor shown unsectioned.

Fig. 6 is a transverse section taken along the line 66 of Fig. 4.

Fig. 'l is an interior view of the detachable half of the casing, drawn on a scale slightly smaller than Figs. 1 to 3.

Fig. 8 is a perspective view of the bridge which serves the hereafter recited plural purposes.

Fig. 9 is a fragmentary section, taken along the line 9--9 of Fig. 3, showing how the ferrule on the handle is fastened to one casing half and has fingers interlocking with both casing halves to hold the rear portions of these casing halves against separation.

Fig. 10 is a section taken along the line l0l0 of Fig. 9.

Fig. 11 is a perspective view of a portion of the mouth end of the stationary casing half, showing one of the notches which interfits a portion of the partition.

In the illustrated embodiment, the casing of my hair drier comprises two generally counterpart casing halves which open toward each other and have their mouth ends interfitting, each of which casing halves effectively affords one longitudinal half of the tubular air spout and the corresponding half of a motor and fan casing which merges and opens into the rear end of the said spout. Thus, Fig. 7 shows the stationary casing half as comprising a semi-tubular spout half S leading from a gap in the peripheral wall C of a generally cap-shaped casing part which has its side (or cap-top) portion E provided with air ports A. The companion detachable casing half, as shown in Figs. 1 and 2, includes a spout half S and incomplete cap wall C and a casing side E and in each casing half the spout preferably has its upper edge tangential to the upper edge of the rearward casing part, which lateral part has the general shape of an axially horizontal drum.

The peripheral wall C of the stationary casing half has at its mouth end of its incomplete caplike rear portion a plurality of spaced notches N (Fig. 11) for receiving radially projecting fingers F (Fig. 3) on a flat partition P which has other portions of its periphery fitting the bore of the said peripheral wall. Fastened to this partition, as by the screws l of Fig. l, are the feet 2 of a bridge (shown separately in Fig. 8) which has a part of each leg 3 bent intermediate of its length to present a shoulder 4 parallel to the two feet, to which shoulders the stator core 5 of the motor is fastened by bolts 6 as in Fig. 5.

Connecting the non-foot ends of these legs is a bridge part I which extends parallel to the feet 2 and which is fastened to the stationary casing side E (as in Fig. 5) by screws 8 attached from outside the casing. This bridge part 1 has its medial portion 1a offset toward the plane of the bridge feet 8 and provided with a central perforation 9 alining with a perforation ID in the adjacent casing side E. Moreover, the annular part E (Figs. 5 and 7) surrounding the perforation ID in this casing side and the annular portion 11) surrounding the central perforation in i in the bridge are concaved toward each other and have their opposed faces formed as parts of a common spherical surface.

An outer bearing H has a correspondingly spherically shaped portion clamped between these opposed annular faces; and a washer W, sleeved upon this hearing, is interposed between the offset part la of the bridge and the casing side E (as shown in Fig. 5), for storing lubricating oil.

The partition P likewise has a central perforation and has a similarly perforated rearward retainer plate R clamped to it, and these parts likewise have annular portions disposed for contering an inner bearing l2 and housing a second washer W Journaled in the two bearings II and I2 is the motor shaft I3, to which shaft the rotor M of the motor is fastened. This shaft reaches only part way toward the other casing side E and the later side desirably has an aperture 25 of sufiiciently larger diameter than the said shaft so that the slender spout of an oil can can be inserted through this aperture.

Operatively fastened to the motor shaft [3, at the opposite side of the partition from the motor, is a fan blade 15, the rotation of which will draw air into the adjacent (detachable) casing half (through air ports A and force this air out through the spout constituted by the spout halves S and S To fasten these spout halves together, I provide an outlet ring I6 sleeved upon the forward ends of the two spout halves and held in position by having opposed ring indentations ll snap into side perforations I8 (Fig. 7) in the spout halves, this ring having spaced guard bar portions l9 extending across it in front of the spout.

To warm the air while passing through the spout, I provide an electric heating unit, here shown as comprising a coil of high resistance Wire R wound on a tubular insulator 20 having its terminal-carrying base 20a bolted to the forward leg 2la of a bracket 2| which has a rearward foot 2lb fastened to the partition P. To simplify this latter fastening I indent contiguous portions of the partition and of this foot into each other, as shown at 2k: in Fig. 6, to prevent relative rotation about a single rivet 22 extending through both the partition and the said foot.

When current is supplied to the usual stator coils 23 carried by the stator core 5 of the motor and also (desirably through the usual series connection to such coils) through the heating wire W, air drawn in through the side ports A at the fan side of the casing is forcibly propelled toward and past the heating coil from the cap-like casing part which houses the fan. This movement of air also produces a suction in the other cap-like casing part which houses the motor, thereby causing air also to be drawn in through the air ports A (Fig. '7) in the stationary casing half; and this latter air intermingles consider-- ably with the air from the fan side of the casing, particularly when the heating unit is freely spaced forwardly by a considerable distance from both the fan blade l5 and the motor.

Consequently, the energy required for effecting the said suction slows up the speed with which air passes the heating wire, thereby giving this wire relatively more time for its warming effect on the air, so that the motor can be of a higher speed than would otherwise permit the air to be adequately heated.

If the partition P were imperforate, the relatively large size of the stator core and coil assembly would cause substantially all of the air entering at the stationary side of the casing to flow laterally outward of these parts, while leaving relatively stagnant air between the stator core and the partitions so that the motor itself would become so hot as to reduce its efficiency considerably. This I overcome by providing the partition perforations 20 which permit a limited interchange of air from opposite sides of the partition, thereby causing a continuous movement of air past the motor to cool the latter.

To support my hair drier for manual use, I provide a handle I-I; preferably having its axis substantially in the general plane of the partition P and having at its upper end a ferrule 26 formed to bear against adjacent portions of both casing halves. This ferrule has two fingers 21 (Fig. 10) respectively adapted to be inserted through slots 28 in the two casing halves before the ferrule is fastened to one of these halves by a screw 29, so that only a single screw is required.

With my above described construction, the motor, the bridge, the fan, the bracket 2| and the heating unit are first as a unit, including the (not illustrated) circuit connections, with the inner bearing l2 clamped in position and the outer bearing (along with the corresponding washer W) already positioned on the bridge. After these parts are assembled in the position shown in Fig. 5, the stationary casing half is slipped over them until this seats on the bridge parts I, to which it is then fastened by the screws 8. The resulting rigid assembly can then be freely handled in any position as a unit for attaching the detachable casing half, the frontal ring l6 and the ferruled handle.

Thus constructed, my hair drier has the handle underhanging the midwidth of the casing, with the axis of the handle substantially in the medial vertical and longitudinal plane of the casing, so that the user can easily and accurately sight the direction in which the warmed air will be propelled. Moreover, with the fan at the opposite side of this medial plane from the motor, this fan balances part of the weight of the motor, thus cooperating with the nearness of this motor to the said plane so that the effective weight of the motor does not exert a material lateral tilting strain on a hand grasping the handle.

Moreover, by prying off the frontal ring l6 and detaching the screw 29, the user can readily detach the detachable casing half, thus permitting a convenient inspection of the heating unit (and even a replacing of this unit) without disassembling any other parts. So also, my simple two-part casing, and my use of a single bridge for fastening the motor to both the casing and the partition reduce the cost as well as the bulk of the motor in comparison with heretofore customary constructions; and by supporting the heating unit from the partition I reduce the conduction of heat from the heating member to the spout.

In practice, I preferably also provide the rearward side part of each casing half with nuts 36 adapted to space the major part of the hair drier from a table on which it is laid. However, I do not wish to be limited to this or other details of the heretofore described construction and arrangement, since many changes may be made without departing either from the spirit of my invention or from the appended claims.

I claim as my invention:

1. In an electric hair drier, a casing comprising a rearward part of horizontally axial drum shape and a horizontal spout into the rear end of which a side part of the said casing portion opens, a partition spanning the bore of the drum and extending parallel to the drum ends substantially in a vertical plane diametric of the axis of the spout, a motor supported within the drum at one side of the partition and having a shaft extending through the partition, a fan fast on the said shaft at the opposite side of the partition from the motor, and a heating unit supported within the said spout, both ends of the drum having ports for admitting air.

2. An electric hair drier as per claim 1, including a bracket fastened to the partition and freely spaced from the casing, the bracket supporting the heating unit in freely spaced relation to the casing.

3. An electric hair drier as per claim 1, in which the partition is provided with air ports permitting air to pass from one side of the partition to the other, the total area of said ports being smaller than the total area of the ports in the drum end adjacent to the fan.

4. An electric hair drier as per claim 1, in which the partition has part of its periphery slidably fitting the drum portion of the casing, in which the heating unit is supported from the partition, and in which the partition and the casing have relatively interengaging portions disposed for holding the partition against rotation in its own plane so as to retain the heating unit in a predetermined disposition with respect to the spout.

5. An electric hair drier as per claim 1, in which the motor, partition and heating unit are all fast with respect to one casing half; the other casing half being detachable without disassembling ing portions of its periphery fitted into the said casing half.

'7 An electric hair drier as per claim 1, in which the motor includes a stator core, a bridge having portions intermediate of its length bearing against and fastened to the adjacent drum end of the casing, the bridge including two leg members fastened intermediate of their length to the stator core and fastened at their free ends to the partition.

8. An electric hair drier as per claim 1, in which the motor includes a stator core, a bridge having spaced portions intermediate of its length fastened to one drum end of the rearward casing portion and having feet fastened to the stator, and a shaft bearing supported conjointly by the last named drum end and by a part of the bridge disposed between the said spaced portions of the bridge.

9. An electric hair drier as per claim 1, in which the motor is fastened to the partition, the hair drier including an inner bearing in which the shaft of the motor is journaled, the said inner bearing being fastened to the partition so as to be detachable from the casing conjointly with the partition and the motor.

10. An electric hair drier as per claim 1, in which the casing comprises two casing halves adjoined substantially along a plane longitudinal and medial of the spout and midway between the drum ends of the rearward casing part; one casing half having notches in its mouth end, and the partition having fingers respectively seated in the said notches, and in which the said fingers are clamped between portions of the two casing halves.

11. In an electric hair drier, a casing having a rearward portion of the general shape of a horizontally axial drum and a horizontal tubular spout, of smaller diameter than the said drum, into which a peripheral upper portion of the drum merges, each drum end having air ports therein; the casing comprising two halves adjoined substantially along a plane diametric of the spout and midway between the ends of the drum; and a mechanism assembly insertable as a unit in one of the casing halves before the other casing half is attached thereto; the said assembly comprising: a bridge having portions near its midlength bearing against the drum end of the said one casing half, a partition fastened to the ends of the bridge and extending across the drum part of the casing substantially in the said plane; a motor fast with respect to the partition and disposed within the arch of the bridge, the motor having a shaft extending through the partition; a fan fast on the shaft at the opposite side of the partition from the motor; and a heating unit fast with respect to the partition and freely housed by the said spout.

12. In an electric hair drier, a casing comprising a rearward axially horizontal and drum-like portion and a spout of smaller diameter than of the said drum-like portion; an upright partition subdividing the rearward portion into two compartments both opening into said spout; an electric motor supported within one compartment and including a shaft extending through the partition into the other compartment, both of the said compartments having air ports in the outer walls thereof; a fan fast on the said shaft and disposed in the said other compartment; and an electric heating element supported within the:

spout in freely spaced relation to the bore of the spout; the axis of the said shaft being vertically offset from that of the spout and the motor being constructed for rotating the shaft in such a direction that the fan will draw air into the said other compartment and propel the indrawn air forwardly through the spout, whereby the suction of the air thus propelled through the spout will also draw air into the casing through the air ports at the motor side of the casing, so that the said suction effect will reduce the rate at which air moves past the said heating element.

BERNHART A. BENSON. 

